The objectives of the research proposal are four-fold. 1) We will examine the relationship between the interaction of pyridoxal phosphate (Vitamin B6) with glucocorticoid receptors and transformation of receptor into a nuclear binding protein. Anti-vitamin B6 antibodies will be employed to detect pyridoxal phosphate steroid receptor interaction. 2) We will utilize pyrodoxal phosphate as a molecular probe to gain new information about the physico-chemical properties of glucocorticoid receptors. 3) We will investigate the potential usage of the antivitamin B6 analog 5-deoxypyridoxal as a regulator and modifier of glucocorticoid receptor structure and function in whole cell. 4) Finally, we propose to utilize (32P) pyridoxal phosphate to dual label glucocorticoid receptors and purify these (32P) pyridoxal phosphate-(3H) dexamethasone receptor complexes to homogeneity. The purification of receptors will involve use of two techniques, pyridoxal phosphate affinity chromatography and anti-pyrodoxal phosphate antibodies which should simplify the task of steroid receptor purification.